Sewer lift alarm system

ABSTRACT

An alarm system for sanitary sewers, and the like, to provide an alert indicating the approach of a potentially dangerous situation which might result in damage or backup of sewage in a particular location in the sewage system. The signal system indicates excessive buildup of sewage in any sewer lift in the sewage system in such a manner that the location of the defective lift may be readily ascertained. In addition, the system is adapted for monitoring the overall situation at the sewer lift in order to determine the exact trouble, such as a power failure outside the system, power failure inside the system, inadequate operation of the pumping equipment, and the like. A repair of maintenance crew may be dispatched to the particular malfunctioning lift for correction of the difficulty prior to sufficient buildup of the sewage in the lift as to inflict damage in the surrounding area.

United States Patent Payne, Sr. Feb. 22, 1972 f 1 [54] SEWER LIFT ALARMSYSTEM Primary Examiner-John W. Caldwell [72] Inventor gz g gif grg igfii Assistant Examiner-Howard Cohen Attorney-William S. Dorman [22]Filed: July 3, 1969 Y 211 App]. No.: 838,838 [57] ABSTRACT An alarmsystem for sanitary sewers, and the like, to provide 521 u.s.c1..340/244 indicating aPPmach pmenia'ly [51] Int. Cl. ..G08b 21/00situation which might result in damage or backup of Sewage in 581 Fieldof Search ..340/244, 233, 213, 413; a the sewage symmsignal sysemzoo/61.05 indicates excessive buildup of sewage in any sewer lift in thesewage system in such a manner that the location of the defec- [56]References cited tive lift may be readily ascertained. In addition, thesystem is adapted for monitoring the overall situation at the sewer liftin UNITED STATES PATENTS order to determine the exact trouble, such as apower failure outside the system, power failure inside the system, in-$23 1? g adequate operation of the pumping equipment, and the like. A3,341,836 9/1967 Marcurhjz.................::::340/244 c repairmaimenance crew may be dispatched the Panic OTHER PUBLICATIONS Stacy, C.E., Ahom Foretells Sewer Overflows American lar malfunctioning lift forcorrection of the difficulty prior to sufficient buildup of the sewagein the lift as to inflictdamage in the surrounding area.

City, May 1967 page 38. 4 Claims, 5 Drawing Figures 22 20 I A 4 l8 441/42 4O E [2 /Y 4 43 50 lo Patented Feb 2 Sheets-Sheet 1 FIG.3

INVENTOR. 26 CLARENCE o. PAYNE. SR.

ATTORNEY Patented Feb. 22, 1972 I 3,644,916

2 Shets-Sheeg INVENTOR. o. PAYNE, $2.

ATTORNEY SEWER LIFT ALARM SYSTEM This invention relates to improvementsin sewer systems and more particularly, but not by way of limitation, toan alarm system for utilization in conjunction with a sewer system forindicating the approach of a potentially damaging condition at any sewerlift site in the sewer system and for indicating the particular troubleencountered at the site.

In most cities or urban areas today, the sanitary system includes aplurality of sumps, or underground sewage collection areas called sewerlifts, for receiving the sewage from the surrounding area. Each of thesewer lifts serves a particular area, and all of the sewer drainpipesextending from the houses, building, or the like, in the area areconnected with the particular sewer lift for draining the sewage intothe lift. Each lift, in turn, is connected with the main sewage disposalplant, or the like, through suitable sewer conduits. An electric pump isnormally disposed in association with each sewer lift for pumping theaccumulation of sewage from the lift to the main sewer lines fortransportation to the main sewage disposal plant. The pump iselectrically or otherwise connected with the particular lift with whichit is associated in such a manner that the pump is automaticallyactuated when the sewage accumulates within the lift to a predetermineddepth. The pump normally maintains the fluid below the established depthin the lift, with said established depth being below the elevation ofany building, or the like, being serviced by the sewer lift. Thus,accumulation of fluid is normally discharged from the sewer lift atintervals sufficient for precluding any backup of the sewage into theservice lines, and thus precluding any backup of the sewage from thelift and into the buildings or houses in the surrounding area.

However, as a practical matter, the pump may malfunction and may notproperly discharge the sewage from the sewer lift. The connectionbetween the lift and pump may be damaged or faulty whereby the pump isnot activated as the sewage accumulates within the lift, or the pumpitself may not operate properly when activated and may not function todischarge the sewage from the lift, or by way of further example, themain or outside power supply to the pump may be disrupted whereby thepump is inactive or inoperable. When malfunction of the pump occurs forany reason, the quantity ofsewage accumulates within the lift to asufficient depth for backing up in the sewage line servicing the areasurrounding the lift. The inoperative condition of the pump usuallyeludes detection, and the continued backup of the sewage in the sewageservice lines may cause the sewage to back up in the individual sewerlines of the building or houses connected therewith. Of course,

' the first backup of sewage will occur in the building of lowestelevation, and if this should occur in a building which is at leasttemporarily unoccupied, the backup of sewage may be considerable, andover an extended period of time before the sewage system failure isnoted. When such a backup of sewage occurs, not only is a greatinconvenience encountered, but also the city or owner of the sewageutility is usually subject to the payment of damages causes by thesewage backup. This is often extremely expensive, not only in the laborrequired for cleaning up the area, but also in the cost of replacementfor ruined furnishings, and the like.

An alarm system has been developed for warning of impending danger at asewer lift site, as set forth in my copending application Ser. No.709,023, filed Feb. 28, 1968 now abandoned, and entitled Sewer LiftAlarm System. The alarm system provides a central surveillance areawherein an alarm is activated when sewage in any sewer lift beingmonitored thereby accumulates beyond a predetermined depth. The alarmsystem identifies the location of the defective sewer lift whereby arepair crew may be dispatched to the site in order to repair themalfunction before damage occurs to the surrounding area. However, ithas been found advantageous to provide an indication of the nature ofthe malfunction in addition to the location of the sewer lift involved.

The present invention contemplates a novel alarm system for a sewagesystem to provide an indication of the particular trouble at the sewerlift in addition to the location of the malfunctioning lift. The novelalarm system comprises an individual detector member disposed withineach of the sewer lifts in a sewage system, with each detector beingdisposed above the level whereupon the pump is normally activated fordischarging the accumulation of sewage from the lift. Each detector isindependently electrically connected with a signal device installed at acentral location, with said central location being manned at all times.Each detector is electrically connected with an individual signal memberat the central location with each individual signal member beingidentified as to the particular sewer lift in which the associateddetector is disposed. In the event of accumulation of sewage within thesewer lift above the predetermined level therefor, the particulardetector disposed within the affected sewer lift will activate itsassociated signal member at the central location, and the operator atthe central location will be immediately alerted of the approachingdangerous situation at the affected sewer lift. In addition, the signalis coded whereby the nature of the particular trouble may be identified.For example, the signal may indicate that the supply of power fromoutside the unit has been interrupted; or the signal may indicate that apumping unit is running, but is not operating properly for dischargingthe sewage from the lift; or the signal may indicate that power failureexists within the unit itself; or the signal may indicate some othercondition which exists at the sewer lift site and which contributes tothe inadequate functioning at the site. In this manner, emergency stepsmay be taken for repairing the damage or malfunction at the site, orotherwise removing the accumulated sewage from the sewer lift prior toany backup of the sewage in the sewage service lines extending from thebuildings or houses in the area surrounding the affected sewer lift.

It is an important object of this invention to provide a novel sewerlift alarm system particularly designed and constructed to provide asafety alarm for a sewer system which augments the normal pumpingequipment utilized in connection with the sewer lifts of the sewersystem.

Another object of this invention is to provide a novel sewer alarmsystem wherein a signal is energized indicating the presence of apossible trouble area in the sewer system whereby attention may beprovided at the potential trouble area prior to any damage to thesurrounding area.

It is another object of this invention to provide a novel sewer alarmsystem wherein a signal is activated at a central location whichindicates the approach of a possible dangerous condition at a remotesewer lift whereby the potential danger area may be readily identified.

A further object of this invention is to provide a novel sewer alarmsystem wherein a signal is activated at a central location whichindicates an inefficient operation at a remotesewer lift site and whichidentifies the particular trouble existing at the site.

A still further object of this invention is to provide a novel seweralarm system which is simple and efficient in operation and economicaland durable in construction.

Other and further objects and advantageous features of the presentinvention will hereinafter more fully appear in connection with adetailed description of the drawings in which:

FIG. 1 is a sectional elevational view of a sewer lift provided with asignal device of the invention and depicting a portion of the areasurrounding the sewer lift schematically.

FIG. 2 is a perspective view of a central signal panel device embodyingthe invention.

FIG. 3 is a broken sectional elevational view of a portion of the signalpanel housing shown in FIG. 2 and depicting one means of fasteningthereof.

FIG. 4 is an electrical schematic view of a sewer alarm system embodyingthe invention.

FIG. 5 is an enlarged electrical schematic view of one portion of asewer alarm system embodying the invention.

Referring to the drawings in detail, and particularly FIG. 1, referencecharacter 10 generally indicates a sewer lift comprising a housing 12normally buried in the ground 14 to provide a sump or storage cavity orchamber 16. The upper end 18 of the housing 12 is normally accessible atthe surface of the ground 14, or may protrude slightly thereabove, andmay be provided with an access opening 20 having the usual removablecover 22 disposed therein.

At least one service sewer line 24 is connected with the housing 12 inany well-known manner (not shown) for discharging fluids or sewage intothe chamber 16 from the surrounding area. The line 24 is normallyinstalled or laid at a slight angle with respect to the horizontal inorder that the sewage moving therethrough will flow by gravity into thechamber 16 for accumulation therein. A plurality of houses, buildings,or the like (not shown) in the surrounding area are connected to theservice sewer line by individual conduits (not shown) as is well knownwhereby the sewage from each house will be deposited or discharged intothe line 24 and thence transported to the chamber 16. Of course, thehouses or buildings are usually at varying levels or elevationsaccording to the terrain of the area surrounding the sewer lift 10.

The sewer line 24 normally enters the chamber 16 at a position spacedupwardly from the bottom of the chamber 16 in order to assure asufficient area therebelow for the desired accumulation of sewage in thechamber, as shown at 26. In addition, it is the usual practice toprovide a suitable pumping unit, generally indicated at 28, in theproximity of the sewer lift 10. The pumping unit 28 may be of anysuitable type and as depicted herein comprises a plurality of pumps 30disposed within a housing 32 generally similar to the housing 12, andburied in the ground 14, as shown in FIG. I, or may be suitablyinstalled on the surface of the ground 14, or installed at any otherdesired location, as is well known. The pumping units 30 may be of anysuitable well-known type, and are connected with the housing 12 andchamber 16 by means ofa conduit 34 whereby the pumps 30 may be utilizedfor withdrawing or discharging the sewage 26 from the chamber 16, aswill be hereinafter set forth in detail. In addition, the pumping units30 are operably connected with suitable motors 36, or the like, foractuation thereby, as is well known. The motors 36 may be installed in asuitable protective shelter or housing 38 and are operably connectedwith the pumping units 30 through leads 40, as is well known. Inaddition, the pumping units 30 or the motors 36 are suitably connectedwith the housing 12 and chamber 16 in such a manner (not shown) that thepumps 30 will be activated when the level of sewage 26 in the chamber 16reaches the established or predetermined level, such as shown in myaforementioned copending application.

For example, a float member (not shown) may be reciprocally mountedwithin the chamber 16 in any suitable manner (not shown) whereby thefloat member will be elevated or raised by the accumulated sewage 26when the level of the sewage reaches the predetermined level within thechamber 16. The upward movement of the float may close a suitable switch(not shown) mounted within the housing 12, with said switch beingelectrically connected with the motors 36 through a suitable lead, orthe like (not shown). The closing of the switch will energize the motors36 for activation of the pumping units 30 to begin the pumpingoperation. The pumps 30 will continue the pumping operation until thelevel of the sewage within the chamber 16 returns to a normal or safelevel. The sewage is pumped from the chamber 16 through the conduit 34and upwardly through a standpipe or conduit 42 into the main sewer line44 where it iscarried or transported to the main sewage disposal plant,or the like (not shown). A suitable pressure switch 41 is interposed inthe line 42 and in communication with the pumps 30 through a conduit 43for a purpose as will be hereinafter set forth.

The position of the float (not shown) within the chamber 16 is normallysuch that the pumps 30 will be activated for elevating the sewage 26from the chamber 16 before the level of the sewage reaches the level ofthe lowermost service sewerline 24, thus precluding any backup of thesewage in the line 24. Of course, any malfunction of the pumps 30, orany failure of the electrical system for activation of the pumps 30usually results in a buildup of sewage in the chamber 16, and a backupof the sewage in the lines 24. As long as the situation remainsunremedied the backup of sewage in the line 24 continues, and may backup in the individual sewer lines (not shown). The backup of the sewagemay be so severe as to back up in the houses or buildings with the firstsigns of the sewage back up being at the housing having the lowestelevation.

A suitable electrode 46. or the like, is suspended in or suitablyinstalled within the chamber 16 at a position slightly above theestablished level of the sewage which elevates the float for normallyactivating the pumps 30. However, the position of the electrode 46 isalso below the level of the lowermost service sewer line 24. Theelectrode 46 is carried by a suitable electrical lead 48 which extendsfrom the housing through a suitable conduit 50. The conduit 50 may bepartially buried in the ground 14, as clearly shown in FIG. 1, andextends vertically from the ground along the usual telephone pole 52 andmay be secured to the pole 52 in any suitable or well-known manner (notshown). The conduit 50 may be grounded in any suitable manner (notshown). The lead 48 is suitably electrically connected through the usualtelephone lines 54 with a centrally disposed alarm device generallyindicated at 56in FIGS. 2 and 4.

The alarm device 56 as shown herein comprises a main box or housingportion 58 having a front plate member 60 secured thereon in a manner aswill be hereinafter set forth. The front plate member 60 is providedwith a centrally disposed rectangular boxlike opening 62 having a coverpanel 64 therefor. The panel 64 is preferably sectional and is providedwith a transversely extending hinge member 66 whereby one portion 68 ofthe panel 64 may be alternately opened and closed to provide access tothe interior of the opening 62. The movable panel portion 68 is providedwith a first window or transparent pane 70 to permit visual inspectionofa signal board generally indicated at 72 and a second window 73 topermit visual inspection of an annunciator panel (not shown) similar tothat shown in my aforementioned copending application. The signal board72 is suitably mounted within the box 58 and at the opening portion 62and is provided with signal means corresponding to each sewer lift 10 ina manner and for a purpose as will be hereinafter set forth. Theannunciator panel is suitably mounted in the opening portion 62 foractuation in a manner similar to that in my aforementioned application.

The interior of the housing 28 enclosing the pumping units 30 isnormally dry whereby the operation of the pumping units 30 will bemaintained at optimum efficiency. However, under certain conditions,leakage may occur and the housing 28 may become at least partiallyfilled with liquid, or the like, which may interfere with the operationof the pumping units 30. A second electrode 74, similar to the electrode46, is suitably suspended or otherwise installed within the interior ofthe housing 28 and is preferably disposed relatively near the bottomthereof, or in the proximity of the elevation of the pumping units 30disposed therein. The electrode 74 is carried by a suitable electricallead (not shown) which extends from the housing 28 through a suitableconduit 76. The conduit 76 may be partially buried in the ground 14, asclearly shown in FIG. 1, and extends vertically from the ground alongthe telephone pole 52 and may be secured to the pole 52 in any suitableor well-known manner (not shown). The pressure switch 81 and the leadfrom the electrode 74 are suitably electrically con nected through theusual telephone lines 54 with the alarm device 56 for a purpose as willbe hereinafter set forth. In addition, suitable electrical leads 78 and80 connect the motor 36 with a relay 82in the circuit of the alarmdevice 56. Of course, the relay 82 may be grounded to the piping orother equipment, as shown at 84 in FIG. 1.

Whereas the particular installation depicted in FIG. 4 relates to asewer system having 20 sewer lifts, it is to be noted that substantiallyany number of lifts may be incorporated in a similar system. Inaddition, since each sewer lift is connected in a substantiallyidentical manner with the alarm device 56,

only one of the sewer lift connections therewith will be set forth indetail herein.

The telephone line 54 from the sewer lift in the sewer system extendsinto suitable electrical connection with an electrical lead, such as thelead 86 shown in FIG. 4. The lead 86 is suitably connected with aterminal 88 of a terminal strip 90, or the like, which is suitablymounted within the box 58. The terminal 88 is, in turn, electricallyconnected with a suitable relay 92 in a manner as will be hereinafterset forth. The relay 92 for each sewer lift 10 is depicted in block formin FIG. 4, for purposes of illustration, and one of the relays 92 beingsubstantially identical. The relays 92 are suitably mounted in the box58 and each relay 92 is electrically connected to a second relay,latching solenoid, annunciator, or the like, as generally indicated at94 in FIG. 4 in a manner and for a purpose similar to that set forth inmy aforementioned copending application. In addition, each relay 92 iselectrically connected to the respective signal means generallyindicated at 95 (FIG. 5) of the signal board 72 in a manner and for apurpose as will be hereinafter set forth. The signal means 95 iseliminated in FIG. 4 for purposes of illustration.

A suitable power supply 96 is provided for the alarm system 56, andprovides a l2-volt DC current device. The power supply 96 may comprise apair of suitable 6-volt hand lantern batteries, such as those known asNEDA Eveready batteries connected in series, or by two 6-volt hotshotbatteries such those known as No. l46l Eveready batteries connected inseries. It is also preferably to make provisions for including a third6-volt battery in order to provide an 18-volt DC current for the system,if desired. Of course, the batteries 96 may be mounted in any desiredlocation, however, it is preferable to install the batteries in the box58. A buzzer relay 98 similar to the relays 92 may also be provided forthe alarm system 56 and may be electrically connected with a suitableremote signal plug 100, if desired.

Referring now to FIG. 5, the signal means 95 comprises a pilot light 102of any well-known or suitable type, a suitable double-pole double-throwswitch I04, and a suitable electrical pushbutton member 106, and mountedon the signal board 72. The relay 92 is electrically connected with theterminal 88 by an electric lead 108 and in turn is electricallyconnected with the pilot light 102, switch I04 and pushbutton 106through the electrical leads 110, I12 and 114, respectively. The switch104 is electrically connected with the telephone line 54 through theelectrical line I16, and also to the relay 92 through the electricalline 118. The pushbutton 106 is electrically connected with the pilotlight 102 by the line 120. The pilot light 102, switch 104 andpushbutton 106 are all electrically connected with the power sourcethrough the electrical leads I22, I24 and 126, respectively.

All the electrical components and wiring therefor are installed in thebox 58 as is well known, and upon the completion of the wiringoperation, the cover plate 60 is rivited or otherwise secured to the box58. For example, as shown in FIG. 3, a plurality of apertures 128 areprovided in the rear face of the box 58 for alignment with a pluralityof apertures 130 provided in the cover plate 60. A sleeve 132 isinserted within the aligned apertures I28 and 130, and is preferablydisposed with the opposite ends thereof protruding beyond the rearsurface of the box 58 and the outer surface of the cover 60. One end ofthe sleeve 132 may be flared outward as shown at I33. A substantiallyU-shaped tool or holder member 134 is provided for spanning the width ofthe box 58 with the cover 60 disposed thereon, as clearly shown in FIG.3. A pointed boss or position member 136 is provided on one arm 138 ofthe holder 134 and extends inwardly for disposition within the flaredend 133 of the sleeve 132. A shank member 140 is threadedly secured tothe opposite arm 142 of the holder 134 and is provided with a pointedboss member 144 on the inner end thereof. The boss member 144 is adaptedfor insertion within the open end of the sleeve I32, and rotation of theshank I40 in one direction causes the boss member 144 to move axiallytoward the sleeve 132 for flaring the exposed end of the sleeveoutwardly, thus securing the cover 60 securely to the box 58 in a mannersubstantially precluding unwanted tampering with the wiring orelectrical components within the box 58.

Each of the annunciators 94 and signal means of the device 56 isidentified in any suitable manner (not shown) for correlation with theparticular sewer lift 10 with which it is connected. As hereinbefore setforth, and windows 70 and 73 permit a constant visual monitoring of theboard 72 and an nunciator panel whereby activation of any of theannunciators 95 and signal means 94 will be promptly noted, and thelocation of the sewer lift 10 activating the signal means may be readilyascertained. In addition, the buzzer or other audible means 98 isconnected with each annunciator 94 in order to further attract theattention of the operator monitoring the system. 1

OPERATION The panel or alarm device 56 is normally installed at acentral location and is provided with constant surveillance by anattendant, or the like. The switches 104 are normally in the positionshown in FIG. 5.

In the event trouble occurs at any sewer lift 10 wherein the sewagesystem fails for any reason, the sewage 6 may rise within the chamber 16until the level of the sewage reaches the electrode 46. As soon as thefluid or sewage 26 touches or engages the electrode 46, the electricalcircuit portion of the panel 56 connected with the particular electrode46 is closed whereby the respective relay 92 will be energized fordropping or lowering the respective annunciator 94 and activating thebuzzer 98 at the central monitoring site. Similarly, any accumulation offluid with the normally dry well or housing 28 which might bedetrimental to the pumping units 30 will activate the electrode 74, thusclosing the electrical circuit connected therewith and dropping theassociated annunciator 94 and energizing the buzzer 98. Thus, theattention of the attendant will be attracted by the audible signal andhe may visually inspect the annunciator panel and signal board 72 forascertaining which of the annunciators 94 has been dropped. The operatoror attendant may correlate the identification number or other insigniathereof with the master plane of the sewer lifts, thus readilydetermining exactly which sewer lift is approaching a sewage problem.

The alarm system 56 may be arranged for monitoring a plurality ofconditions at the sewer lift site in order to facilitate the maintenanceand repair thereof. For example, if the pumping units 30 at the affectedsewer lift 10 are operating, then the pressure at the pressure switch 41will be normal and annunciator 94 will be illuminated, thus providing avisual indication that the trouble at the sewer lift is something otherthan an inoperative pump. Of course, if the pumps 30 are not operating,the pressure at the pressure switch 41 will drop for activating thepressure switch in such a manner that the light 102 associated with thedropped annunciator 94 is not lighted. This gives an indication thateither the pumping units 30 are not pumping or the light 102 isdefective or burned out. In order to test the bulb or light 102, thepushbutton I06 associated therewith may be manually depressed. The pilotlight 102 will be illuminated upon depression of the button 106 if thelight is in operating condition. This assures, then, that the pumpingapparatus 30 is inoperative at the sewer lift site. Of course, if thelight 102 does not burn or go on upon depressing of the pushbutton 106,the bulb is defective and may be replaced.

Furthermore, whether the pumping apparatus 30 is pumping or is notpumping, it is desirable to ascertain the reason for the malfunction atthe sewer lift site. Accordingly, the buzzer or other signal member maybe suitably electrically connected in the circuit for providing codedsignals in accordance with a variety of situations which might occur atthe sewer lift site. For example, the closing of the electrical circuitof the affected sewer lift 10 drops the respective annunciator drop 94,as set forth in my copending application, which places suitable cyclingtimers in electrical connection in the circuit. In the event theelectrical circuit of the affected sewer lift 10 has been closed byenergization of the electrode 74 of the dry well or housing 38, thebuzzer may be intermittently energized whereas the buzzer may becontinuously energized if the electrode 46 has closed the circuit.Similarly, a long and short type coded signal may be produced by thebuzzer when the motors 36 are inoperative due to a malfunction withinthe system itself, whereas still a different coded signal may beproduced at the buzzer in the event the power fails outside the systemitself, such as a main electrical supply failure. Of course,substantially any desiredcondition may thus be monitored by the alarmsystem whereby not only is advance notice of impending danger at a sewerlift provided, but also the overall or general nature of the cause ofthemalfunction, or the like, is provided.

A repair or maintenance crew may be quickly dispatched to the vicinityof the identified sewer lift 10 for correction of the problem which mayexist at the site. It will be apparent that an advance indication of theparticular type of trouble will greatly facilitate the operation of thework crew and reduce the overall time required for repair of the sewerlift. Of course, the corresponding switch 104 may be manually opened toextinguish the buzzer 98 as soon as the advance information relating tothe troubled sewer lift is received, and after the proper repairs havebeen made or the situation has been remedied, the thrown or droppedswitch 104 may be reset for restoring the alarm system 56 to the normalmonitoring position therefor.

It is preferable that the time delay between the activation or closingof the electrical circuit connected with an affected sewer lift 10 besufficient to enable the work crew to reach the trouble area insufficient time to preclude unwanted damage. This time delay may beestablished or determined by the position of the electrode 46 within thechamber 16. The electrode 46 is preferably disposed just above thenormal upper limit of the sewage level in the chamber 16 in order thatthe electrode will be energized as soon as the level of the sewage risesabove the desired maximum therefor and at a maximum time before thelevel of the sewage reaches the lowermost sewer line 24. Similarly, theelectrode 74 may be positioned within the housing 28 at an optimumposition for providing an advance warning in adequate time before therise of fluid within the housing 28 will damage or hinder the operationof the pumping units 30.

As hereinbefore set forth, the particular alarm device 56 shown in FIG.4 relates to an alarm system for a sewer system having 20 sewer lifts.Each of the sewer lifts in the system is connected with the respectiverelay 92 for activating the buzzer 98 and with the respective relay 104.Thus, the entire sewer lift system is constantly under surveillance atall times.

From the foregoing it will be apparent that the present inventionprovides a novel safety alarm system for sewer systems whereby warningof approaching trouble in the sewer system is provided. In addition, anindication of the particular nature of the trouble at the affected sewerlift is provided. A central location is provided with an alarm devicewherein a signal is energized upon the rise of any sewage in any sewerlift in the sewage system above the established maximum level for thesewage therein. The signal or alarm provides an identification of theparticular sewer lift, or lifts, wherein a troubled condition isapproaching, and an overall indication of the nature of the trouble orproblem at the sewer lift site, thus enabling the dispatching ofmaintenance or repair crews to the site for .understood that other andfurther modifications, apart from those shown or suggested herein, maybe made within the spirit and scope of this invention.

What is claimed is:

1. An alarm means for a sewer system having at least one sewer lifttherein and comprisin detector means disposed within said sewer lift andactivate upon contact with sewage rising within said sewer lift, acentrally disposed alarm device remotely disposed from said sewer liftand operably connected with said detector, said alarm device beingenergized upon activation of said detector for providing a signal uponthe rise of the sewage within the sewer lift, and means connected withsaid alarm device for indicating the probable cause of substantially anytrouble at the sewer lift, and wherein the sewer system includes aplurality of sewer lifts each having a dry well and a wet well, and saiddetector means comprises an individual detector disposed within the dryand wet wells of each sewer lift being operably connected with saidalarm device for independent actuation of the alarm upon the rise offluid in either the dry or wet well of any of the sewer lifts, andwherein the alarm device comprises housing means disposed at said remoteposition, first electrical relay means provided in said housing meansand having an independent relay operably connected with each of saidindividual detectors whereby each detector activates its respectiverelay to indicate a rise of liquid within the wet well at the respectivesewer lift, said signal means comprises second electrical relay meansprovided in said housing and having individual relay memberselectrically connected with each of said first independent relayswhereby each first relay activates its respective second relay member,and said last-mentioned means comprises signal means disposed withinsaid housing and visible from the exterior thereof, said signal meanscomprising independent signal members operably connected with each ofsaid first relays whereby each of said first relays activates itsrespective signal member for distinctively indicating a rise of liquidwithin the dry well or a power failure or a pump failure at therespective sewer lift.

2. An alarm means for a sewer system as set forth in claim 1 wherein thesignal means comprises indicator light means operably connected with thefirst relay in such a manner as to be lighted only for indicatingtrouble other than pump failure, pressure-responsive button meansoperably connected with said indicator light means to provide anindicator for checking the operable condition ofsaid light, and resetswitch means for restoring the alarm means to the normal positiontherefor subsequent to activation thereof for any reason.

3. An alarm means for a sewer system as set forth in claim 2 whereinpumping means is provided in said dry well, and pressure switch meansoperably connected between said pumping means and said signal means forprecluding activation of said indicator light when pump failure ispresent in the sewer system.

4. An alarm means for a sewer system as set forth in claim 1 wherein thesignal means includes a first distinctive signal to indicate mainelectrical power failure and a second distinctive signal to indicateelectrical power failure within the sewer lift system itself.

1. An alarm means for a sewer system having at least one sewer lifttherein, and comprising detector means disposed within said sewer liftand activated upon contact with sewage rising within said sewer lift, acentrally disposed alarm device remotely disposed from said sewer liftand operably connected with said detector, said alarm device beingenergized upon activation of said detector for providing a signal uponthe rise of the sewage within the sewer lift, and means connected withsaId alarm device for indicating the probable cause of substantially anytrouble at the sewer lift, and wherein the sewer system includes aplurality of sewer lifts each having a dry well and a wet well, and saiddetector means comprises an individual detector disposed within the dryand wet wells of each sewer lift being operably connected with saidalarm device for independent actuation of the alarm upon the rise offluid in either the dry or wet well of any of the sewer lifts, andwherein the alarm device comprises housing means disposed at said remoteposition, first electrical relay means provided in said housing meansand having an independent relay operably connected with each of saidindividual detectors whereby each detector activates its respectiverelay to indicate a rise of liquid within the wet well at the respectivesewer lift, said signal means comprises second electrical relay meansprovided in said housing and having individual relay memberselectrically connected with each of said first independent relayswhereby each first relay activates its respective second relay member,and said last-mentioned means comprises signal means disposed withinsaid housing and visible from the exterior thereof, said signal meanscomprising independent signal members operably connected with each ofsaid first relays whereby each of said first relays activates itsrespective signal member for distinctively indicating a rise of liquidwithin the dry well or a power failure or a pump failure at therespective sewer lift.
 2. An alarm means for a sewer system as set forthin claim 1 wherein the signal means comprises indicator light meansoperably connected with the first relay in such a manner as to belighted only for indicating trouble other than pump failure,pressure-responsive button means operably connected with said indicatorlight means to provide an indicator for checking the operable conditionof said light, and reset switch means for restoring the alarm means tothe normal position therefor subsequent to activation thereof for anyreason.
 3. An alarm means for a sewer system as set forth in claim 2wherein pumping means is provided in said dry well, and pressure switchmeans operably connected between said pumping means and said signalmeans for precluding activation of said indicator light when pumpfailure is present in the sewer system.
 4. An alarm means for a sewersystem as set forth in claim 1 wherein the signal means includes a firstdistinctive signal to indicate main electrical power failure and asecond distinctive signal to indicate electrical power failure withinthe sewer lift system itself.